Again I got new information about 4th class. Gravity added some sprite names for npcs. No sprites yet.
JT_EM_DILUVIO = 20816,
JT_EM_ARDOR = 20817,
JT_EM_PROCELLA = 20818,
JT_EM_TERREMOTUS = 20819,
JT_EM_SERPENS = 20820,
JT_4JOB_VOID = 20821,
JT_4JOB_WRAITH = 20822,
JT_4JOB_KINGS_NIGHT = 20823,
JT_4JOB_AGONY_NIGHT = 20824,
JT_4JOB_DEVOTION_NIGHT = 20825,
JT_4JOB_ARMED_NIGHT = 20826,
JT_4JOB_DOOMK = 20827,
JT_4JOB_VERKHASEL = 20828,
JT_4JOB_BAPHOMET = 20829,
JT_4JOB_H_FALCON = 20830,
JT_4JOB_S_FALCON = 20831,
JT_4JOB_R_FALCON = 20832,
JT_4JOB_WORG = 20833,
JT_MEISTER_ABR1 = 20834,
JT_MEISTER_ABR2 = 20835,
JT_MEISTER_ABR3 = 20836,
JT_MEISTER_ABR4 = 20837,
JT_ELEMETAL_MASTER_S1 = 20838,
JT_ELEMETAL_MASTER_S2 = 20839,
JT_ELEMETAL_MASTER_S3 = 20840,
JT_ELEMETAL_MASTER_S4 = 20841,
JT_ELEMETAL_MASTER_S5 = 20842,
More information should come within the next weeks or months.